Refrigerator evaporator



May 21, 1935. H. s. WOODRUFF REFRIGERATOR EVAPORATOR Filed Aug. 28, 1929 Inventor: Henrg S. Woodr'uff,

His Attorney.

Patented May 21, 1935 UNITED STATES PATENT OFFICE REFRIGERATOR EVAPORATOR New York Application August 28,

44 Claims.

My invention relates to refrigerator evaporators of the type which is adapted to be arranged in a refrigerator cabinet to constitute a shelf therein for ice-freezing trays or other articles that are to be frozen thereon and for cooling the refrigerator cabinet.

An object of my invention is to provide an evaporator for refrigerating apparatus made of two sheet metal portions, one of the sheet metal portions having an indentation formed therein constituting a header and another sheet metal portion having a straight portion extending across the indentation and secured to the first mentioned sheet of metal, the straight portion being constructed to provide a rigid wall extending across the indentation.

Another object of my invention is to provide an evaporator of simple construction having an arrangement of passages therein which will cause effective circulation of refrigerant in the evaporator so as to cool the surfaces thereof as desired, and to provide an evaporator which can be readily fabricated from metal plates. I accomplish this by providing an evaporator including a fiat upper surface for supporting articles to be frozen and a header extending along one edge of the evaporator which communicates with a plurality of passages extending from the header to the opposite side of the plate.

My invention will be more fully set forth in the following description referring to the accompanying drawing and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and forming part of this specification.

In the drawing, Fig. 1 is a perspective view of a refrigerator cabinet having my improved evapo rator arranged therein and provided with a refrigerating system including the evaporator for cooling the cabinet; Fig. 2 is a perspective View of my improved evaporator at one stage of its manufacture; Fig. 3 is a plan view of my improved evaporator; Fig. 4 is a sectional view on the line 1-4 of Fig. 3; and Fig. 5 is a sectional view approximately on the line 55 of Fig. 4.

Referring to the drawing, in Fig. 1 my improved evaporator I is supported by rods II from a removable cover ll! of a refrigerator cabinet 13 so as to constitute a horizontal shelf therein for supporting ice-trays or other articles to be frozen in the cabinet and for cooling the cabinet. A refrigerating machine It is associated with the evaporator to cool the cabinet, which is controlled in response to the temperature of the evaporator b the control device It. In accordance with 1929, Serial No. 389,047

my invention, the evaporator is formed with a flat upper surface for supporting ice-trays or other articles to be frozen, and in order to cool this surface efiectively I provide for a rapid circulation of refrigerant on the lower surface of a top plate l of the evaporator, constituting the flat upper surface of the evaporator. This effective circulation of refrigerant is obtained by providing a header l6 along one edge of the evaporator which communicates with a plurality of substantially parallel passages ll extending from the header adjacent the opposite edge of the evaporator, which constitute a refrigerant chamber. The passages 11 communicate with each other at the ends thereof opposite the header by a passage or manifold l8. The ,level of liquid refrigerant in the evaporator is maintained at a level'approximately midway between the top and the bottom of the header, so that all the passages I1 and I8 maintain the liquid refrigerant directly in contact with the lower surface of the top plate l5. This insures a rapid transfer of heat from the surfaces of the evaporator to the liquid refrigerant therein. It will be observed that this arrangement of the header and the passages provides for the circulation of refrigerant from the header through all of the passages in a plurality of closed paths in the manner indicated by the arrows in Fig. 3. I have found that this circulation is very rapid and continuously circulates refrigerant from the header beneath the top plate iii of the evaporator so as to effectively cool articles placed thereon and also cool the cabinet in which the evaporator is arranged. It will also be noted that the circulation of refrigerant in the evaporator as indicated will remove vaporized refrigerant from the passages I! and I8 as soon as it is vaporized and will carry the same to the header it where it can pass to the refrigeraing apparatus associated with the evaporator. This utilizes the cooling surfaces of the evaporator most effectively, as it avoids accumulation of vaporized refrigerant in the passages of the evaporator, which would interfere with the transfer of heat from the surfaces thereof to the refrigerant therein. During the operation of the refrigerating machine associated with the evaporator, liquid refrigerant is supplied to the evaporator through the pipe or conduit l9, providing a passageway extending through one of the passages I! to the passage I8 into which it discharges the liquid refrigerant. The vaporized refrigerant is withdrawn from the header N5 of the evaporator through the pipe 20 having a. battle 2| arranged directly below the same to prevent the liquid refrigerant being withdrawn from the header l5, it being understood that the level of the liquid refrigerant in the header is slightly below the baffle 2|.

If the refrigerator door is frequently opened warm air may be admitted to the cabinet to such an extent as to cause an abnormal increase in load on the refrigerating machine associated with the cabinet. The load on the refrigerating machine is also increased when an article to be frozen such as an ice cube tray of water or the like is placed on the evaporator. Either of these causes may therefore effect an undesirable extreme fluctuation in load on the refrigerating machine. In order to prevent such fluctuation in the load, I provide a chamber ll below the refrigerant chamber I! which contains a freezing solution such as salt and water or any other heat absorbing body which will be reduced in temperature by the refrigerant in the chamber l1 and provide a large capacity for absorbing heat. By this arrangement when the temperature of the air in the refrigerator cabinet is considerably raised by frequent opening of the door, or when an ice cube tray filled with water is placed on the top of the evaporator, the freezing solution in the chamber l1 will cooperate with the refrigerant in the chamber H to reduce the temperature of the water in the ice cube tray, or the temperature of the air in the refrigerator cabinet, as desired, without greatly increasing the load on the refrigerating machine.

I prefer to construct this evaporator in such a manner that it can be readily fabricated from metal plates. I do this by stamping a sheet of metal to form a top plate I5 with a recess or indentation 22 extending along one edge thereof to constitute a header. The indentation 22 is formed with the edges of the sheet l5 and adjacent three edges of the sheet so as to provide an elongated header in the sheet which is closed at its opposite ends by the walls of the indentation formed in the sheet. I weld rods H to the corners of the top plate for supporting the evaporator in the refrigerator cabinet in which it is used. I then stamp another plate 23 of the evaporator with a recess 24 along one edge thereof and a plurality of substantially parallel recesses or corrugations 25 extending therefrom adjacent the opposite edge of the plate. The portions 26 between the recesses 25 are in the same plane as .the outer edge of the plate, so that when the top plate is attached to this plate the edges thereof and the portions 26 are all in close contact with the top plate so that the recess 24 and recesses or corrugations 25 cooperate with the top plate l5 to form the passages l8 and I1, respectively, communicating with the header "5. I weld the portions 26 of the plate: 23 throughout their length to the top plate, as indicated at 21. Welding the plates l5 and 23 together in this manner prevents the pressure of the refrigerant in the evaporator from spreading them apart and maintains the top plate substantially flat. Moreover, the corrugations forming the passages I! extend across the header indentation l6 formed in the sheet l5, as the sheets are welded together entirely about the header indentation where the corrugations in the sheet 23 are in contact with the sheet I5 on both sides of the header and the sheets l5 and 23 are welded together at their edges in completing the evaporator, the portion of the sheet 23 extending across the header indentation l6 provides a. portion constructed to form a rigid wall across the header indentation and passageways for the flow of refrigerant from the header. I stamp a bottom plate 28 with a recess 29 and a flat edge portion about the recess so that it is adapted to cooperate with the plate 23 to form the chamber l'! for a freezing solution. I then weld the three plates I5, 23 and 28 together about the edges thereof as indicated at 30 which forms the chambers I! and H for the refrigerant and the freezing solution respectively. This evaporator is of strong mechanical construction, as the three plates are welded together about the edges thereof and the plates l5 and 23 are welded together between the corrugations forming the passages I1.

I do not desire my invention to be limited to the particular arrangement shown and described, and I intend in the appended claims to cover all modifications which do not depart from the spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States, is:

1. An evaporator for refrigerating machines including a flat upper surface for supporting articles to be frozen and a header extending along one edge of the evaporator, said evaporator having a plurality of passages extending from said header to the opposite side of said fiat surface for the circulation of refrigerant therethrough and having a passage extending along the edge thereof communicating with the passages extending from said header.

2. An evaporator for refrigerating machines including a flat top plate for supporting articles to be frozen, said top plate having a recess along one edge to constitute a header, and another plate secured to said top plate and having a passage along the edge opposite said header and a plurality of other passages extending from said first mentioned passage to said header.

3. An evaporator for refrigerating machines including a flat top plate for supporting articles to be frozen, said top plate having a recess along one edge to constitute a header, and another plate secured to said top plate and having corrugations extending from said header adjacent the opposite edge thereof and a recess affording communication between said corrugations.

4. An evaporator for refrigerating machines including a flat top plate for supporting articles to be frozen, said top plate having a recess along one edge to constitute a header, and another plate having corrugations extending from said header adjacent the opposite edge thereof cooperating with said top plate to form passages and a recess affording communication between said passages, said other plate being secured to said top plate about the edges thereof and at the line of contact between said corrugations and said top plate so as to prevent the pressure of refrigerant separating said plates.

5. An evaporator for refrigerating machines including a flat upper surface for supporting articles to be frozen, a header extending along one edge of the evaporator, said evaporator having a plurality of passages extending from said header to the opposite side of said flat surface for the circulation of refrigerant therethrough, means for supplying refrigerant to said passages at the opposite ends thereof from said header, and means for withdrawing vaporized refrigerant from said header.

6. An evaporator for refrigerating machines including a flat top plate for supporting articles to be frozen, said top plate having a recess along one edge to constitute a header, another plate having corrugations extending from said header adjacent the opposite edge thereof cooperating" with said top plate to form passages and a recess affording communication between said passages, said other plate being welded, to said top plate about the edges thereof and at the line of contact between said corrugations and said top plate so as to prevent the pressure of refrigerant separating said plates, means for supplying refrigerant to said passages at the ends thereof opposite said header, and means for withdrawing vaporized refrigerant from said header.

'7. In combination with a refrigerator cabinet, an evaporator therein arranged to constitute a shelf including a flat top plate for supporting articles to be frozen, said top plate having a recess along one edge to constitute a header, and another plate secured to said top plate and having a passage along the edge opposite said header and a plurality of other passages extending from said first mentioned passage to said header.

8. In combination with a refrigerator cabinet,

an evaporator therein arranged to constitute a shelf including a flat top plate for supporting articles to be frozen, said top plate having a recess along one edge to constitute a header, and another plate having corrugations extending from said header adjacent the opposite edge thereof cooperating with said top plate to form passages and a recess affording comunication between said passages, said other plate being welded to said top plate about the edges thereof and at the line of contact between said corrugations and said top plate so as to prevent the pressure of refrigerant separating said plates.

9. An evaporator for refrigerating machines including a flat upper surface for supporting articles to be frozen and a header extending along one edge of the evaporator, said evaporator having a plurality of passages extending from said header to the opposite edge of said fiat surface for the circulation of refrigerant therethrough, and a chamber for a heat absorbing body below said passages.

10. An evaporator for refrigerating machines including a flat top plate for supporting articles to be frozen, said top plate having a recess along one edge to constitute a header, another plate secured to said top plate and having corrugations extending from said header adjacent the opposite edge thereof and a recess affording communicationbetween said corrugations, and a bottom plate cooperating with said corrugated plate to form a chamber for a heat absorbing body.

11. An evaporator for refrigerating machines including a flat top plate for supporting articles to be frozen, said top plate having a recess along one edge to constitute a header, another plate having corrugations extending from said header adjacent the opposite edge thereof cooperating with said top plate to form passages and a recess affording communication between said passages, said other plate being secured to said top plate about the edges thereof and at the line of contact .between said corrugations and said top plate so as to prevent the pressure of refrigerant separating said plates, and a bottom plate cooperating with said corrugated plate to form a chamber for a heat absorbing body.

12. An evaporator of the flooded type for refrigerating apparatus comprising two sheets of metal, one only of said sheets having an indentation formed therein constituting a header, said indentation extending from the proximity of one edge of said sheet to the proximity of the other edge of said sh'eet, said header being adapted to contain liquid refrigerant and constituting a chamber for the accumulation of vaporized refrigerant above the level of liquid refrigerant therein, the other of said sheets of metal being corrugated, said sheets of metal being secured together between the corrugations, said corrugations forming passageways for the flow of refrigerant and extending from said header below the surface of the'liquid refrigerant therein exposed to vaporized refrigerant, and means for withdrawing vaporized gefrigerant from said header.

13. An evaporator of the flooded type for refrigerating apparatus comprising two sheets of metal, one only of said'sheets having an indentation formed therein constituting an elongated header closed by a wall of said indentation at one end thereof, said indentation extending from one edge of said sheet in proximity to the other edge of said sheet, said header being adapted to contain liquid refrigerant and constituting a chamber for the accumulation of vaporized refrigerant above the level of liquid refrigerant therein,

the other of said sheets of metal being corrugated, said sheets of metal being secured together between the corrugations, said corrugations forming passageways for the flow of refrigerant and extending from said header below the surface of the liquid refrigerant therein exposed to vaporized refrigerant, and means for withdrawing vaporized refrigerant from said header.

14. An evaporator 0f the flooded type for refrigerating apparatus comprising two sheets of metal, one only of said sheets havingan indentation formed therein constituting a header, said indentation extending in proximity of three edges of said sheet, said header being adapted to contain liquid refrigerant and constituting a chamber for the accumulation of vaporized refrigerant above the level of liquid refrigerant therein,

the other of said sheets of metal being corrugated, said sheets of metal being secured together between the corrugations, said corrugations forming passageways for the flow of refrigerant and extending from said header below the surface of the liquid refrigerant therein exposed to vaporized refrigerant, and means for withdrawing vaporized refrigerant from said header.

15.'/An evaporator of the flooded type for refrigerating apparatus comprising two sheets of metal, one only of said sheets having an indentation therein constituting a header, said indentation extending from the proximity of one edge of said sheet to the proximity of the other edge of said sheet, said header being adapted to contain liquid refrigerant and constituting a chamber for the accumulation of vaporized'refrigerant above the level of liquid refrigerant therein, the other of said sheets of metal being corrugated, said sheets of metal being welded together between the corrugations and substantially throughout the length thereof, said corrugations forming passageways for the flow of refrigerant and extending from said header below the surface of the liquid refrigerant therein exposed to vaporized refrigerant, and means for withdrawing vaporized refrigerant from said header.

16. An evaporator of the flooded type for refrigerating apparatus comprising a sheet of metal having an indentation formed therein constituting a header, the wall of said indentation forming a closure-for one end of said header, said header being adapted to contain liquid refrigerant and constituting a chamberjor the accuof liquid refrigerant therein, another sheet of said metal having a straight corrugated portion ex: tending across said indentation and secured to said first-mentioned sheetof metal, and means for withdrawing vaporized refrigerant from said header.

17. An evaporator of the flooded type for refrigerating apparatus comprising a sheet of metal having an indentation formed therein constituting a header, said header being adapted to contain liquid refrigerant andconstituting a chamber for the accumulation of vaporized refrigerant above the level of liquid refrigerant therein, another sheet of metal having a straight corrugated portion extending across said indentation and welded to said flrstmentioned sheet of metal on both sides of said indentation and closely adjacent thereto, and means for withdrawing vaporized refrigerant from said header.

18. An evaporator of the flooded type for re-' frigerating apparatus comprising a sheet of metal having an elongated indentation formed therein constituting a header, said header being adapted to contain liquid refrigerant and constituting a chamber for the accumulation of vaporized refrigerant above the level of liquid refrigerant therein, another sheet of metal having a straight corrugated portion extending across said header indentation and secured to said first-mentioned sheet of metal, the corrugations in said straight portion extending transversely across said header indentation, and means for withdrawing vaporized refrigerant from said header.

19. An evaporator of the flooded type for refrigerating apparatus comprising a sheet of metal having an indentation formed therein constituting a header, said header being adapted to contain liquid refrigerant and constituting a chamber for the accumulation of vaporized refrigerant above the level of liquid refrigerant therein, a corrugated sheet of metal having a straight corrugated portion extending across said indentation and secured to said first-mentioned sheet of metal to provide a rigid wall across said header indentation and passageways for the flow of refrigerant extending from said header below the surface of the liquid refrigerant therein exposed to vaporized refrigerant, and means for withdrawing vaporized refrigerant from said header. v

20. An evaporator of the flooded type for refrigerating apparatus comprising a sheet of metal having an indentation formed therein within the edges of said sheet, said indentation constituting a header, said header being adapted to contain liquid refrigerant and constituting a chamber for the accumulation of vaporized refrigerant above the level of liquid refrigerant therein, another sheet of metal having a straight portion extending across said header indentation and secured to said first-mentioned sheet of metal closely adjacent the walls of said header indentation, and means for withdrawing vaporized refrigerant from said header.

21. An evaporator of the flooded type for refrigerating apparatus comprising a sheet of metal having an indentation formed therein within the edges of said sheet, saidindentation constituting a header said header being adapted to contain liquid refrigerant and constituting a chamber for the accumulation of vaporized refrigerant above the level of liquid refrigerant therein, another sheet of metal having a corrugated straight portion extending across said header indentation and secured to said first-mentioned sheet of metal closely adjacent and entirely about said header indentation, and'means for withdrawing vaporized refrigerant from said header.

22. An evaporator of the flooded type for refrigerating apparatus comprising a'sheet of metal having an indentation formed therein within the edges of said sheet, said indentation constituting a header, said header being adapted to contain liquid refrigerant and constituting a chamber for the accumulation of vaporized refrigerant above the level of liquid refrigerant therein, another corrugated sheet of metal extending across said header indentation and substantially coextensive with said first-mentioned sheet, said sheets being secured together closely adjacent the wall of said header indentation and entirely about the same, said corrugations providing a rigid wall extending across said header indentation and passageways for the flow of refrigerant extending from said header below the surface of the liquid refrigerant therein exposed to vaporized refrigerant, and means for withdrawing vaporized refrigerant from said header.

23. An evaporator of the flooded type for refrigerating apparatus comprising a smooth sheet of metal having an indentation formed within the edges of said sheet, said indentation constituting a header, said header being adapted to contain liquid refrigerant and constituting a chamber for the accumulation of vaporized refrigerant above the level of liquid refrigerant therein, a corrugated sheet of metal having a corrugated portion extending across said header indentation and secured to said first-mentioned sheet of metal to provide a rigid wall across said header indentation and pasageways for the flow of refrigerant, said corrugated sheet having fiattened edges between said corrugations and flat tened surfaces in the plane of said flattened edges extending substantially the entire length of said passageways, said passageways extending from said header below the surface of liquid refrigerant therein exposed to vaporized refrigerant, and means for withdrawing vaporized refrigerant from said header.

24. An evaporator of the flooded type for refrigerating apparatus comprising a sheet of metal having an indentation formed therein within the edges of said sheet, said indentation constituting a header, said header being adapted to contain liquid refrigerant and constituting a chamber for the accumulation of vaporized refrigerant above the level of liquid refrigerant therein, a corrugated sheet of metal extending across said header indentation and substantially coextensive with said first-mentioned sheet, said sheets being welded together closely adjacent the wall of said header indentation and entirely about the same, said sheets also being welded together between said corrugations and substantially throughout the length thereof, said cormgations providing a rigid vwall extending across said header indentation and passageways for the flow of refrigerant extending from said header below the surface of the liquid refrigerant therein exposed to vaporized refrigerant, and means for withdrawing vaporized refrigerant from said header.

25. An evaporator of the flooded type for refrigerating apparatus comprising a smooth sheet of metal having an elongated indentation formed along one edge of said sheet and within the edges of said sheet, said indentation constituting a header, said header being adapted to' contain liquid refrigerant and constituting a chamber for the accumulation of vaporized refrigerant above the level of liquid refrigerant therein, a

corrugated sheet of metal having a portion provided with corrugations extending across the entire side of said indentation and welded to said first-mentioned sheet of metal entirely about said header indentation and between said corrugations substantially throughout the length thereof to provide a rigid wall across said header indentation and passageways for the flow of refrigerant extending from said header below the surface of liquid refrigerant therein exposed to vaporizedrefrigerant, and means for withdrawing vaporized refrigerant from said header.

26. An evaporator of the flooded type for refrigerating apparatus comprising' a sheet of metal having an indentation formed therein constituting a header, said header indentation being closed at one end by a wall of said indentation, said header being adapted to contain liquid refrigerant and constituting a chamber for the accumulation of vaporized refrigerant above the level of liquid refrigerant therein, a corrugated sheet of metal extending across said header indentation and substantially coextensive with said first-mentioned sheet of metal, said sheets being secured together closely adjacent the wall of said header indentation and entirely about the same, said corrugations providing a rigid wall extending across said header indentation and passageways for the flow of refrigerant extending fromv said header below the surface of the liquid refrigerant therein exposed to vaporized refrigerant, and means for withdrawing vaporized refrigerant from said header.

27. A flooded type evaporator for refrigerating machines having walls including complementary sheet metal portions, means for joining said sheet metal portions together, at least one of said sheet metal portions having indentations therein forming a header and a refrigerant containing chamber, said refrigerant containing chamber communicating with said header and extending therefrom, and means including a refrigerant supply passage extending between said sheet metal portions from adjacent said header to the portion of said chamber remote from said header for supplying refrigerant to said chamber, and means for withdrawing vaporized refrigerant from said header.

28. A flooded type evaporator for refrigerating machines having walls including complementary sheet metal portions, means for joining said sheet metal portions together, at least one of said sheet metal portions having indentations therein forming a header and a refrigerant containing chamber, said refrigerant containing chamber communicating with said header and extending therefrom, means including a refrigerant supply conduit extending through said header between said sheet metal portions and terminating within said refrigerant containing chamber remote from said header for supplying refrigerant to said chamber, and means for withdrawing vaporized refrigerant from said header.

29. A flooded type evaporator for refrigerating machines having walls including complementary sheet metal portions, means for joining said sheet metal portions together, at least one of said sheet metal portions having an indentation therein forming a header and corrugations forming passages communicating with said header and extending therefrom, means including a refrigerant supply passage extending between said sheet metal portions from adjacent said header to the portion of said passages remote from said header for supplying refrigerant to said passages, and means for withdrawing vaporized refrigerant from said header.

30. A flooded type evaporator for refrigerating machines having walls including complementary sheet metal portions, means for joining said sheet metal portions together, at least one of said sheet metal portions having an indentation therein forming a header and corrugations forming passages communicating with said header and extending therefrom, means including a refrigerant supply conduit extending through said header and between said sheet metal portions from ad-; Jacent said header to the portion of said passages remote from said header for supplying refrigerant to said passages, and means for withdrawing vaporized refrigerant from said header.

31. A flooded type evaporator for refrigerating machines having walls including complementary sheet metal portions, means for joining said sheet metal portions together, one of said sheet metal portions including a flat upper surface for supporting articles to be frozen, at least one of said sheet metal portions having an indentation therein forming a header and corrugations forming passages communicating with said header and communicating with eacn other remote from said header, means including a refrigerant supply passage extending between said sheet metal portions adjacent said header to a portion of said passages remote from said header for supplying refrigerant to said passages, and. means for withdrawing vaporized refrigerant from said header.

32. A flooded type evaporator for refrigerating machines having walls including complementary sheet metal portions, means for joining said sheet metal portions together, one of said sheet metal portions including a flat upper surface for supporting articles to be frozen, at least one of said sheet metal portions having an indentation therein forming a header and corrugations forming passages communicating with said header and communicating with each other remote from said header, means including a refrigerant supply conduit extending from said header and between said sheet metal portions to said portion of said passages remote from said .header for supplying refrigerant to said passages, and means for withdrawing vaporized refrigerant from said header. v

33. A flooded type evaporator for refrigerating machines having walls including complementary sheet metal portions, means for joining said sheet metal portions together, one of said sheet metal portions including a flat upper surface for supporting articles to be frozen, at least one of said sheet metal portions having an indentation therein forming a header and corrugations forming passages with said header and communicating with each other remote from said header, means including a conduit extending through said header and one of said passages to said portion remote from said header for supplying refrigerant to said passages, and means for withdrawing vaporized refrigerant from said header.

34. An evaporator for refrigerating machines including a flat upper surface for supporting articles to be frozen, a header on one side of said evaporator, said evaporator having a refrigerant containing chamber extending from said header and communicating therewith, means including a. conduit extending through said header and said refrigerant containing portion for supplying refrigerant to said refrigerant containing portion remote from said header, and means for withdrawing vaporized refrigerant from said header. A

35. An evaporator for refrigerating machines including a flat top plate for supporting articles to be frozen, said top plate having a recess along one edge to constitute a header, another plate having corrugations extending from said header adjacent the opposite edge thereof and cooperating with said top plate to form passages, one of said plates having a recess affording communication between said passages remote from said header, said other plate being welded to said top plate about the edges thereof and along the line of contact between said corrugations and said top plate so as to prevent the pressure of refrigerant separating said plates, means for supplying refrigerant to said passages at the ends thereof opposite said header, and means for withdrawing vaporized refrigerant, from said header.

36. In combination with a refrigerator cabinet, an evaporator therein arranged to constitute a shelf including a flat top plate for supporting articles to be frozen, said top plate having a recess along one edge to constitute a header, and another plate secured to said top plate and having a plurality of passages extending from said header, and means providing for communication between portions of said passages remote from said header. 37. In combination with a refrigerator cabinet, an evaporator therein arranged to constitute a shelf including a flat top plate for supporting articles to be frozen, said top plate having a recess along one edge to constitute a header, and another plate having-corrugations extending from said header adjacent the opposite edge thereof and cooperating with said top plate to form passages, and means affording communication between portions of said passages remote from said header, said other plate being welded to said top plate about the edges thereof and along the line of contact between said corrugations and said top plate so as to prevent the pressure of refrigerant separating said plates.

38. An evaporator for refrigerating machines including a flat upper surface for supporting articles to be frozen, a header extending along one edge of the evaporator, said evaporator having a plurality of passages extending from said header to the opposite side of said flat surface for the circulation of refrigerant therethrough, means including a conduit extending through said header and said passages for supplying refrigerant to said passages at the opposite ends thereof from said header, and means for withdrawing vaporized refrigerant from said header.

39. A flooded type evaporator for refrigerating'machines having walls including complementary sheet metal portions, means for joining said sheet metal portions together, at least one of said sheet metal portions having an indentation therein forming a header, said header providing a chamber for the accumulation of vaporized refrigerant above the level of liquid refrigerant therein, at least one of said sheet metal portions having an indentation therein forming a refrigerant containing chamber communicating with said header and extending therefrom below the level of the vaporized refrigerant therein, means including a refrigerant supply passage extending between said sheet metal portions from adjacent said header to a portion of said refrigerant conaooam taining chamber remote from said header for supplying refrigerant to said refrigerant containing chamber, andmeans for withdrawing vaporized refrigerant from said header.

40. A flooded type evaporator-for refrigerating machines having walls including complementary sheet metal portions, means for joining said sheet metal portions together, at least one of said sheet metal portions having an indentation therein forming a header and corrugations forming passages communicating with said header and extending therefrom, at least one of said sheet metal portions having an indentation therein forming a manifold interconnecting portions of said passages remote from said header, means including a refrigerant supply passage extending between said sheet metal portions from adjacent said header to said manifold for supplying refrigerant to said manifold,.and means for withdrawing vaporized refrigerant from said header.

41. A flooded type evaporator for refrigerating machines having walls including complementary sheet metal portions, means for joining said sheet metal portions together, at least one of said sheet metal portions having an indentation therein forming a header, said header providing a chamber for the accumulation of vaporized refrigerant above the level of liquid refrigerant therein, at least one of said sheet metal portions having corrugations therein forming passages communicating with said headerand extending therefrom below the level of the liquid refrigerant therein, at least one of said sheet metal portions having an indentation therein forming a manifold interconnecting portions of said passages remote from said header, means including a refrigerant supply passage extending between said sheet metal portions from adjacent said header to said manifold for supplying refrigerant to said manifold, and means for withdrawing vaporized refrigerant from said header.

42. A flooded type evaporator for refrigerating machines having walls including complementary sheet metal portions, at least one of said sheetmetal portions having an indentation therein forming a header, said header providing a chamber for the accumulation of vaporized refrigerant above the level of liquid refrigerant therein, at least one of said sheet metal portions having corrugations therein forming passages communicating with said header and extending therefrom below the level of the liquid refrigerant therein, said sheet metal portions being welded together between the corrugations and substantially throughout the length thereof, at least one of said sheet metal portions having an indentation therein forming a manifold interconnecting said passages remote from said header, means including a refrigerant supply passage extending be tween said sheet metal portions from adjacent said header to said manifold for supplying refrigerant to said manifold, and means for withdrawing vaporized refrigerant from said header.

43. An evaporator of the flooded type for refrigerating apparatus comprising a sheet of metal having an indentation formed therein within the edges of said sheet, said indentation constituting a header, said header being adapted to contain liquid refrigerant and constituting a chamber for the accumulation of vaporized refrigerant above the level of liquid refrigerant therein, another sheet of metal having a straight portion extending across said header indentation and secured to said first mentioned sheet of metal closely adjacent the walls of said header inde'ntation, at least one of said sheets of metal hav ing corrugations therein forming a series of re frigerant passages communicating with saidheader below the level of the liquid refrigerant therein, and means for withdrawing vaporized refrigerant from said header.

44. A flooded type evaporator for refrigerating machines having walls including complementary sheet metal portions, means for joining said sheet metal portions together, at least one of said sheet metal portions having an indentation therein forming a header and corrugations forming passages communicating with said header and extending therefrom, at least one of said sheet metal portions having an indentation therein forming a manifold interconnecting portions of said passages remote from said header, means for supplying refrigerant to said manifold, and means for withdrawing vaporized refrigerant from said header.

HENRY S. WOODRUFF.

DISCLAIMER 2,002,444.Henry S. Woodrafl, Schenectady, N. Y. REFRIGERATOR Evarona'ron. Patent dated May 21, 1935. Disclaimer filed February 6, 1936, by.theassignee, General Electric Company. Hereby enters this disclaimerof claim l-of said patent. [Qflicial Gazette February 25, 1936.] 

